Index: clang/lib/Driver/ToolChains/Clang.cpp
===================================================================
--- clang/lib/Driver/ToolChains/Clang.cpp
+++ clang/lib/Driver/ToolChains/Clang.cpp
@@ -4551,10 +4551,11 @@
   // Select the appropriate action.
   RewriteKind rewriteKind = RK_None;
 
+  bool DefaultUnified = Triple.isPS4();
   bool UnifiedLTO =
           Args.hasFlag(options::OPT_funified_lto,
                        options::OPT_fno_unified_lto,
-                       false);
+                       DefaultUnified);
   if (UnifiedLTO)
     CmdArgs.push_back("-funified-lto");
 
@@ -7043,7 +7044,8 @@
 
   bool DefaultsSplitLTOUnit =
       (WholeProgramVTables || SanitizeArgs.needsLTO()) &&
-      (LTOMode == LTOK_Full || TC.canSplitThinLTOUnit());
+      (LTOMode == LTOK_Full || TC.canSplitThinLTOUnit()) ||
+       UnifiedLTO;
   bool SplitLTOUnit =
       Args.hasFlag(options::OPT_fsplit_lto_unit,
                    options::OPT_fno_split_lto_unit, DefaultsSplitLTOUnit);
Index: clang/lib/Frontend/CompilerInvocation.cpp
===================================================================
--- clang/lib/Frontend/CompilerInvocation.cpp
+++ clang/lib/Frontend/CompilerInvocation.cpp
@@ -1754,6 +1754,13 @@
       Diags.Report(diag::err_drv_invalid_value) << A->getAsString(Args) << S;
   }
 
+  if (Opts.UnifiedLTO) {
+    if (T.getOS() == llvm::Triple::PS4)
+      Opts.EnableSplitLTOUnit = false;
+    else
+      Opts.EnableSplitLTOUnit = true;
+  }
+
   if (Arg *A = Args.getLastArg(OPT_fthinlto_index_EQ)) {
     if (IK.getLanguage() != Language::LLVM_IR)
       Diags.Report(diag::err_drv_argument_only_allowed_with)
Index: llvm/include/llvm/Transforms/Utils/ModuleUtils.h
===================================================================
--- llvm/include/llvm/Transforms/Utils/ModuleUtils.h
+++ llvm/include/llvm/Transforms/Utils/ModuleUtils.h
@@ -105,7 +105,7 @@
 /// If the module has no strong external symbols (such a module may still have a
 /// semantic effect if it performs global initialization), we cannot produce a
 /// unique identifier for this module, so we return the empty string.
-std::string getUniqueModuleId(Module *M);
+std::string getUniqueModuleId(Module *M, bool UnifiedLTO = false);
 
 /// Embed the memory buffer \p Buf into the module \p M as a global using the
 /// specified section name.